Electrical connector



oct. 13, 1942. I 6 2,298,615

I ELECTRICAL CONNECTOR Filed June 18, 1941 Lewis 6095 dz?! Patented Oct. 13, 1942.

UNITED STATES ATE T OFFICE ELECTRICAL CONNECTOR Lewis cogs-am, Horseheads, N. Y. Application mile 18, 1941, Serial No. 338,659 4- olaims. (01173-343) The present invention relates to improvements in electrical connectors and more specifically to a connector for use in electric light sockets.

The primary purpose of the invention is to provide an electrical connector of the abovementioned type which may be easily assembled to efiect a connection between a light socket and an extension cord or cable without requiring that the parts be first centered as is the case in the present-day two-part plug connectors. k

A further object of the" invention is to provide an electrical connector which may be coupled to efie'ct an electrical connection between a light socket and extension cord which will establish a connection between the plug and connection in?- gardless of the radial position of thecoupling member when the parts of the coupling and con nection are assembled.

A still further object of the invention is topro vide an adapter for electric light sockets which is adapted to carry a single contact so that one of the plug contacts will establish a direct connection with the socket member or electric light socket.

Other objects and advantages of the invention will become apparent during the course of the following description of the accompanying drawing, wherein:

Figure l is a side elevational view of an electric light socket illustrating an embodiment of the invention attached thereto by breaking away a portion of the electric" light socket to expose the connection in detail;

Figure 2 is a transverse cross sec'tional view taken on line 2-4 of Figure 1, looking in the direction of the arrows, further illustrating in detail the location of the concentric shell members;

Figure 3 is a bottom plan View of the connector, showing the cover therefor;

Figure 4 is a side elevational View of the plug member embodying the invention;

Figure 5 is a side elevational iew of the adap tor for receiving the plug member; and

Figure 6 is a vertical cross-sectional view taken on line 6-6 of Figure 3, looking in the direction of the arrows, further illustrating the invention in detail.

In the drawing, wherein for the purpose of illustrating the invention and wherein like reference characters will be employed to designate like parts throughout the same, the reference character 5 will generally be employedto designate an electric light socket comprising an outer shell 6 reduced as at 1 emanating an intermediate tapered portion a.

Mbunted in the siren c andextendirig downwardly' to the reduced portion 1 is a cylindrical insulating she'n 9 er the neon type. The shell 9 is open at the r p and bottoiii and the cylindrical shell portion 6 is adapted to ceive a round porcelain mem er ID which forms the base f r a switch adapted to' b'e operated y a; handle! I.

The switch base I'il' is provided on its bottom wall with a contact if secaream place by means of a screw {3 an'd in diametrically opposed relation with respect to'th'e screw l3 is an extension strip [4, held in position inthe base of the switch base It] by means of a screw 15. The extension [4 depends downwardly and adapted tQSl'lpDOIt a threaded shell l'6 locatedin the reduced pormen 1 of th' 6c1 t. V y 7 Contacts [1' are mounts opposite sides of the switch base sn table recesses i8 so that the cables l9 may be connected thereto by screws 2|]. The structure thus far described constitutes theconveritionai and1u fia1forin r electric light socket, the present invention being designed to permit the use of a socket of this typeafter the light bulb has been removed-for the purpose of connecting up the serv ce lines of an electrical appliance to the socket with the latter providing the supply of curre'h't for the lines, with the supply controlled by the switch of the socket. Such practice is well-known and is ge'nera lly provided in etch manfirfa's to eliminate the need for turning of tuliistirig the serv ce ines; in threading the "connector into the so'cket t'he usual two-part pronge d courier-r1611; will illustrate the practice, the adapter b'ein'g threaded into the socket and the ronged' lemeritinsrted into the adapter; the present invention provides a substitute for such practice. a

The present invention cbfnprises a threaded adapter 2! which is famed of insulating material in cylindricalform and having a frustoco'nica'l end wall 22 ap'ertured as at 23. A metal shell 24 is mounted on the external periphery of the adaptor 2|", the shell being rolled into the threads of the adaptor, providing a metal surfaceto the threaded portion of the adaptor, itself of insulating material; the threads conform to those of the lamp socket, so that when the-adaptor is threaded into the socket, the peripher'y of the adapter has the" proper contact with the" socket contact usually carried by the socket shell. The opposite end portion of the adapter 2 1 is prcvidd with an outwardly-extending annular flange 25 designed to overlie the end of the socket shell I and serves to limit the inward movement of the adaptor into such shell. The adapter is thus an annular member with one end open and of generally uniform internal diameter excepting at the opposite end which has the frusto-conical formation formed with the central opening 23; being of insulating material it can be threaded into the shell of the socket even into contact with contact |2 (in the event of a shortened socket shell) without setting up short circuit characteristics; with the usual length socket shell, the adapter will thread into the socket shell until flange 25 contacts the end of the shell, leaving the frusto-conical end as spaced from contact l2.

Embedded in the inner wall of the adaptor 2| adjacent the upper end thereof is an arcuately curved plate 26 fastened in place by means of a rivet 21 which extends through the wall of the adaptor and its shell 24, and having a contact relation with the latter, thus carrying a current path from the socket shell contact to the plate 26, the latter having dimensions such as to provide for an extended area exposure annularly and lengthwise of the internal face of the adaptor.

The plug or male member 28 comprises a round insulating member 29 having a frusto-conical inner end wall 30 capable of fitting the frusto-conical top wall 22 of the adaptor 2|. A projection 3| is formed in the center of the plug 28 on the frusto-conical wall 30 and is adapted to project through the opening 23 in the end wall of the adaptor in direct alignment with the contact l2.

The outer end portion of the plug 28 is provided with an annular flange 32 designed to overlie the adapter outer end flange and to limit the inward movement of the plug 28 in the adaptor 2|. Formed adjacent the upper end of the plug 28 is a recess for receiving an annular contact ring 33 wh ch extends substantially around the entire periphery of the plug 28. An electrode 34 extends generally longitudinally of plug 28 and is formed with lateral end zones. one of which is connected to the ring 33. as at 35. while the opposite lateral end zone 36 is located at the outer end of the plug and receives a screw 31 adapted to permit of the attachment of one of the wires38-of a service cable 39a to such electrode end.

Extending lon itud nally throu h the plug 28 is an electrode 39. having one end angularly bent as at 4!! for receiving a screw threaded rod 4!, the u per end of which is provided with a contact 42 for engaging the contact member l2. The lower end of the electrode 39 is angularly bent as at 43 for receiving a screw 44 adapted to attach the other wire 45 of the service cable electrically to the electrode.

The outer face of the plug 28 is recessed as at 46 and 41 for accommodating ends of the electrodes and the screws 31 and 44 respectively so that the screws will lie in the plane of such outer face.

Attached to the bottom wall of the plug 28 is a cover 48 having a flange 49 which frictionally engages the annular flange 32 and said cover may be held in place by means of an anchoring screw 49a. extending through a boss 58 in the cover 48 and anchored in a block embedded in the plug 28. The cover 48 is provided with a tubular extension 52 for the passage of the electrical service cable exemplified by wires 38 and 45.

In operation, the adaptor is first threaded into CPI the socket shell; with socket shells of the standard length, such threading will place flange 25 in contact with the end of the socket shel1- thus closing the thread zones, with the frustoconical end out of contact with socket contact I2-but with such end of the adaptor sufficiently close to the socket contact as will permit the plug 28 to advance to place its contact 42 in contact with contact l2 when the plug conical end is contacting the similar end of the adapter. After the adapter is positioned, the plug is advanced longitudinally into the adapter-with no necessity for turning the plug since the uniform diameter of the internal face of the adapter and the uniform diameter of the plug permits the plug to be pushed into the adapter until its contact 42 contacts contact l2; with the standard length of socket shell, the plug inner end will seat against the corresponding end of the adaptor, and flange 32 will overlie flange 25, as indicated in Fig. 1, and thus close the circular line of contact between the plug and adapter, this advance of the plug placing band 33 in contact with the plate 26, thus completing thev two current paths to the respective service cords or wires. There is no need for rotation of the plug in order to complete contact through plate 25, since the annular band 33 will complete the contact in any angular position of the plug in the adapter.

The same operation is had in case the socket shell is shorter than the standard length. In such case the threading of the adaptor will end by contact of its conical end with contact I2- leaving flange 25 out of contact with the shell socket; the advance of the plug into the adaptor will bring the plug contact 42 into contact with contact |2 before flange 32 contacts flange 25; but in other respects the assemblage will provide the same electrical results in either case. This is due to the fact that the body portions-internal of the adaptor and external of the plugare each of uniform diameter, so that the plug body fits within the adaptor body regardless of the length of advance of the plug into the adapter; and the fact that the length of plate 25 longitudinally of the adapter is materially greater than the width of band 33, so that the latter can complete contact with the plate 26 in varied positions of longitudinal adjustment.

Among the advantages of the specific connector is this fact of operating with equal efliciency regardless of variations in the length of the socket shell from the standard length; the fact that the major portion of the length of the connector is itself within the socket shell length, thus providing the support of such shell to the stabilit of the connector, and the fact that the connector itself is practically rigid and stable, being protected against wobbling or accidental disarrangement, since separation can take place only by movement of the plug axially, with the requirement of a lengthy movement from the working position of the plug necessary to affect the normal relation of plug and adaptor. Hence, the operator is not required to exercise the careful attention against disarrangement that is presented by the well-known connectors.

It is to be understood that the form of the invention herewith shown and described is to be taken as the preferred embodiment of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claimt 1. As a means for operably connecting an extension cord or the like to the screw-threaded shell zone of a light socket, a multi-member assembly adapted to establish circuit connections with the respective socket contacts when the assembly is positioned relative to the shell zone of the socket and to provide a break in such connections and removal of the cord by movement of assembly members relative to each other nonrotatively, said assembly comprising a female externally-threaded adapter member adapted to be threaded into the socket thread zone, and a rigid male member carrying the cord terminals and adapted to complementally fit the adapter member when assembled therewith, the major portion of said members when assembled being housed within the shell zone of the light socket; said female member being of insulating material of general shell form having its inner end of truncated conical form to provide an approximately closed inner end with a central opening, and having its outer end externally flanged to overlie the shell zone of the light socket, said member additionally carrying an internal local contact plate having a rivet connection with the member thread zone to thereby place said plate in circuit with the light socket shell zone contact when the adapter is in position, the shell body of the member being of substantially uniform thickness to thereby provide a bore of substantially uniform diameter; said male member having the external surface of its body portion substalntially complemantal to such bore and conical end and provided with a central projection adapted to extend through the truncated conical end with the projection carrying a contact adapted to co-operate with the central contact of the light socket, said male member also carrying a narrow peripheral substantially-annular contact ring positioned to lie in contact with said local contact plate when the members are assembled, the outer end of said male member being externally flanged to overlie the flange of the female member and also carrying the terminal securing means for the cord terminals, the body of the male member having independent connections from the respective terminals to the ring and the end terminal, whereby the male member movement to and from assembly position may be had by an axial slidable movement and with the assembled members held rigidly in position.

2. An assembly as in claim 1 characterized by a sheet-metal cover overlying the outer end of the male member and its terminal means and having a central opening for the passage of the cord strands en route to such terminal means 3. An assembly as in claim 1 characterized by a cover of sheet metal characteristic overlying the outer end of the male member and its terminal means and with the cover removably secured to such member end, said cover having a central opening for the passage of the cord strands en route to such terminal means.

4. An assembly as in claim 1 characterized in that the facial area of the local contact plate of the female member axially of such member is materially greater than the width of the annular band of the male member, whereby compensation is had for variations in shell lengths of the light socket without afiecting the circuit connections or stability of the assembly.

LEWIS COGSDILL. 

